194 HETEROMERA. 
longer and more erect intermixed hairs), smaller eyes, longer antenne, narrower neck, 
small size, &c. distinguish this species at a glance from the others of the genus here 
described. The apical joint of the maxillary palpi is also longer, and approaches that 
of Stereopalpus; but the shape is more triangular than cultriform (as exhibited in 
S. mellyi, La Ferté, the type of the genus Stereopalpus), and the insect in this respect 
agrees better with Hurygenius. In the finely punctured elytra &c. EH. wniformis 
approaches the Californian Stereopalpus pruinosus, Lec. ; from which, to judge from 
the description, it differs in the sharply defined anterior constriction of the thorax, 
longer antenne, small size, &c., as well as in the more dilated apical joint of the 
maxillary palpi. The legs are less coarsely punctured and more slender than in 
the preceding species. 
BACTROCERUS. 
Bactrocerus, Leconte, New Species Col. p. 143 (1866); Leconte & Horn, Class. Col, N. Am. p. 410 
(1883). 
The single known species of Bactrocerus is from Cape San Lucas, Lower California ; 
the one from the Pacific slope of Guatemala now added agrees well with Leconte’s 
definition of the genus, which may be readily distinguished from Stereopalpus and 
Eurygenius by the long apical joint of the antenne (more especially in the male sex) 
and the short broad apical joint of the maxillary palpi. The description of Leconte 
was, no doubt, based upon male examples only. 
1. Bactrocerus fasciculatus. (Tab. IX. fige. 5,3; 6,2.) 
Piceous- or reddish-brown, the prothorax usually a little darker, thickly clothed with coarse brownish or white 
appressed pubescence, the pubescence on the elytra here and there forming spots. Head densely and 
roughly punctured, finely canaliculate in the middle behind; eyes large, prominent, rather coarsely 
granulated, moderately emarginate in front; antenne slender, widening a little outwardly, joints 1-5 
piceous, the base and apex of each more or less testaceous, 6-10 black, 11 testaceous or flavo-testaceous, 
the latter slightly constricted at the middle in both sexes—in the male about three times, in the female 
twice, the length of the tenth ; prothorax much longer than broad, not very convex, a little flattened on 
the disc, the sides rounded just before the middle (the prothorax as wide here as at the base), moderately con- 
stricted behind, and rather feebly (not abruptly) constricted before the apex, the disc transversely depressed 
in front and shallowly canaliculate (the pubescence appearing to be obliquely combed off on either side of 
a median line), the basilar groove distinct only at the sides, the surface densely and coarsely punctured 
(the punctuation hidden by the pubescence); elytra very much wider than the prothorax, very coarsely 
and deeply punctured, the punctuation becoming still coarser and deeper towards the base, finer and closer 
towards the apex, and here and there confluent, the minute interspaces almost granular at the apex; 
beneath densely punctured and thickly pubescent; legs coarsely and roughly punctured and thickly 
clothed with bristly hairs, piceous, the base and apex of the femora, the basal half of the tibia, and the 
base of the first joint of all the tarsi more or less reddish-brown; fifth ventral segment in the male 
transversely depressed in the middle behind, unemarginate. 
Length g¢ 5-54, 9 83-9 millim. 
Hab. Guatemata, El Tumbador 2500 feet, Cerro Zunil 4000 feet (Champion). 
Three male and two female examples. 
From B. concolor, Lec., this-species may be at once distinguished by the shorter 
